Abstract

Since autoimmune mediated encephalitis was recognised 15 years ago, several autoantibodies have been identified. We present 3 patients with positive VGKC antibodies to emphasise the spectrum of clinic presentation and value of antibody testing.

A 61 yo male presented with cognitive decline and frequent right arm stiffening, which is recognised as faciobrachial dystonic seizure. VGKC/LGI1 antibody positive. Received IVIG treatment and rapidly recovered.

A 69 yo women presented with acute personality change and poor short memory following a brief syncope. MRI showed bilateral hippocampus high T2/FLAIR signal. VGKC/LGI-1 antibody was 5800. She improved with IVIG and steroid treatment. However, seizures recurred when weaning from steroid at 4 months. Repeat titre of 1100. Steroid restarted until antibody negative.

A 60 yo male presented with 8 months of personality change without myoclonus. VGKC antibody was positive with a titre of 169. Further testing LGI1 and CASPA2 were negative. He gradually recovered with 6 month steroid treatment. No specific cause was found with extensive investigations.

The typical presentations of VGKC encephalitis have been widely recognised, however clinical vigilance is important for atypical presentations. Antibody titres are of great value following the treatment, while low positive cases prompt further investigations.